The most impressive thing about the Boston Bruins’ 11-game winning streak entering Saturday night was how easy the Bruins had made it look. Boston rolled over just about everyone who had stood in its path leading up to that point.

The B’s got a stiff test on Saturday in Arizona, but they found a way to grind out a 4-2 win over the Coyotes and extend their winning streak to 12 games. It was the most impressive win of the winning streak, not because of dominance, but because of perseverance.

If the Bruins’ winning streak did end in Glendale on Saturday night, it wouldn’t be a huge surprise. The Bruins were going up against a Coyotes team that came in riding a three-game winning streak as it fought for the final playoff spot in the Western Conference. That was evident as the Coyotes scored in the first period, the first first-period goal the Bruins had allowed in 10 games. Then Oliver Ekman-Larsson’s power-play goal in the opening minute of the second period put Phoenix ahead 2-1, the first time the B’s had trailed in almost 411 game minutes, a stretch that dated all the way back to March 9.

Things didn’t look good with the Bruins trailing 2-1 entering the third period. Phoenix had a 21-4-3 record when leading after two periods, while the Bruins were just 6-13-1 when trailing after 40 minutes. Oh, and the Bruins were playing their second game in as many nights in two different time zones, and their fourth game in six days across three time zones. Had they packed it in, no one would really blame them.

The Bruins didn’t pack it in.

The comeback effort really started in the second period. Midway through the second, the Bruins started to find their game. That came to a head when Boston’s first line turned in an incredible shift late in the period. Boston possessed the puck for almost two entire minutes in the Phoenix zone, and while they didn’t convert, they did start to shift the momentum.

That momentum shift carried over into the third period, which provided a boost for a team that needed it badly. Jarome Iginla was credited with the game-tying goal at 3:48 mark of the third period. Iginla did a masterful job of creating traffic in front and was credited with the goal when Zdeno Chara’s shot deflected off of him and by Coyotes goalie Mike Smith.

The Bruins’ first line then set the table for the go-ahead goal. The unit pinned the Coyotes deep for another Herculean shift that had Phoenix back on its heels. That allowed the Bruins’ fourth line to hop on and take advantage. Shawn Thornton deflected a Daniel Paille shot by Smith for the eventual game-winner with just 3:18 left on the clock.

That sequence personified the recent stretch of dominance. The Bruins have been able to cut through this difficult stretch in large part because of their incredible depth. The ability to put all four lines out on the ice at any point allows Claude Julien’s bunch to get to that extra level of intensity, even when the deck seems stacked against them.

Talent helps, too, of course. Talent played a big role in the Bruins’ first 11 wins on this winning streak. On Saturday night, it took a little bit more to make it a dozen.